Here's a guess: tomatoes. They were thought to be poisonous. They are in fact a member of the nightshade family of plants.
Greece
greece
The second oldest European capital is Athens, Greece, established around 3000 BC.
The oldest known Indo-European language is believed to be Proto-Indo-European, which is the hypothetical common ancestor of all Indo-European languages.
Athens
Peoria is the oldest European settlement in Illinois. It was settled in 1691.
Vincennes, IN was established in 1732 and is the oldest European town in Indiana
Macao
Yes
macao
Avestan
Denmark, in fact it's the world oldest national flag.